.NET Core中的Mongo C#驱动程序和ObjectID JSON字符串格式

Question

问题

我有一组动态数据.我想这样回来:

{
  _id: "58b454f20960a1788ef48ebb"
  ... 
}

尝试

以下列出了不起作用的方法:

这个

await resources = _database.GetCollection<BsonDocument>("resources")
    .Find(Builders<BsonDocument>.Filter.Empty)
    .ToListAsync();

return Ok(resources);

产量

[[{"name":"_id","value":{"bsonType":7,"timestamp":1488213234,"machine":614561,"pid":30862,"increment":16027323,"creationTime":"2017-02-27T16:33:54Z","rawValue":{"timestamp":1488213234,"machine":614561,"pid":30862,"increment":16027323,"creationTime":"2017-02-27T16:33:54Z"},"value":{"timestamp":1488213234,"machine":614561,"pid":30862,"increment":16027323,"creationTime":"2017-02-27T16:33:54Z"}}}]]

这个

await resources = _database.GetCollection<BsonDocument>("resources")
    .Find(Builders<BsonDocument>.Filter.Empty)
    .ToListAsync();

return Ok(resources.ToJson());

产量

[{ "_id" : ObjectId("58b454f20960a1788ef48ebb"), ... }]

这个

await resources = _database.GetCollection<BsonDocument>("resources")
    .Find(Builders<BsonDocument>.Filter.Empty)
    .ToListAsync();

return Ok(resources.ToJson(new JsonWriterSettings() { OutputMode = JsonOutputMode.Strict }));

产量

[{ "_id" : { "$oid" : "58b454f20960a1788ef48ebb" }, ... }]

这个

await resources = _database.GetCollection<BsonDocument>("resources")
    .Find(Builders<BsonDocument>.Filter.Empty)
    .ToListAsync();

return Ok(Newtonsoft.Json.JsonConvert.SerializeObject(resources));

产量

"Newtonsoft.Json.JsonSerializationException:在'MongoDB.Bson.BsonObjectId'上从'AsBoolean'获取值时出错.---> System.InvalidCastException:无法将类型为'MongoDB.Bson.BsonObjectId'的对象强制转换为'MongoDB.Bson .BsonBoolean"

并BsonDocument改为dynamic产生相同的结果.

我也尝试根据文档注册序列化程序.我真的很喜欢这个解决方案,因为我总是希望我的ObjectIds格式合理而不是无法使用.如果可能的话,我想让这个工作.

这个

_client = new MongoClient(clientSettings); 
_database = _client.GetDatabase(_settings.DatabaseName); 
BsonSerializer.RegisterSerializer(new ObjectIdSerializer());

...

class ObjectIdSerializer : SerializerBase<ObjectId>
{
    public override ObjectId Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
    {
        return context.Reader.ReadObjectId();
    }

    public override void Serialize(BsonSerializationContext context, BsonSerializationArgs args, ObjectId value)
    {
        context.Writer.WriteString(value.ToString());
    }
}

对上述任何结果都没有影响.

Answer 1

保存到MongoDB时使用BsonDocument

在尝试了许多不同的配置之后,我能够使用连接器正确保存真正动态文档的唯一方法是将对象解析为BsonDocuments.

public ActionResult Post([FromBody]JObject resource)
{
    var document = BsonDocument.Parse(resource.ToString(Formatting.None));

    DbContext.Resources.InsertOne(document);
}

BsonDocument使用JSON.Net 注册序列化程序

与上述方法的问题是最初调用,当ToJson()所述ISODate和ObjectId对象将被序列化为目的,这是不希望的.在撰写本文时,似乎没有任何可扩展性点来覆盖此行为.逻辑被烘焙到MongoDB.Bson.IO.JsonWriter类中,您无法BsonSerializer为BsonValue类型注册s :

MongoDB.Bson.BsonSerializationException:无法为类型BsonObjectId注册序列化程序,因为它是BsonValue的子类.

在撰写本文时,我发现的唯一解决方案是明确定制JSON.Net转换器.MongoDB C#负责人Robert Stam创建了一个未发布的图书馆,社区成员Nathan Robinson已将其移植到.net-core..我已经创建了一个正确序列化ObjectId和ISODate字段的fork.

我从他们的工作中创建了一个NuGet包.要使用它,请在您的.csproj文件中包含以下参考:

<PackageReference Include="MongoDB.Integrations.JsonDotNet" Version="1.0.0" />

然后,明确注册转换器:

Startup.cs

using MongoDB.Integrations.JsonDotNet.Converters;

public class Startup
{
    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc().AddJsonOptions(options =>
        {
            // Adds automatic json parsing to BsonDocuments.
            options.SerializerSettings.Converters.Add(new BsonArrayConverter());
            options.SerializerSettings.Converters.Add(new BsonMinKeyConverter());
            options.SerializerSettings.Converters.Add(new BsonBinaryDataConverter());
            options.SerializerSettings.Converters.Add(new BsonNullConverter());
            options.SerializerSettings.Converters.Add(new BsonBooleanConverter());
            options.SerializerSettings.Converters.Add(new BsonObjectIdConverter());
            options.SerializerSettings.Converters.Add(new BsonDateTimeConverter());
            options.SerializerSettings.Converters.Add(new BsonRegularExpressionConverter());
            options.SerializerSettings.Converters.Add(new BsonDocumentConverter());
            options.SerializerSettings.Converters.Add(new BsonStringConverter());
            options.SerializerSettings.Converters.Add(new BsonDoubleConverter());
            options.SerializerSettings.Converters.Add(new BsonSymbolConverter());
            options.SerializerSettings.Converters.Add(new BsonInt32Converter());
            options.SerializerSettings.Converters.Add(new BsonTimestampConverter());
            options.SerializerSettings.Converters.Add(new BsonInt64Converter());
            options.SerializerSettings.Converters.Add(new BsonUndefinedConverter());
            options.SerializerSettings.Converters.Add(new BsonJavaScriptConverter());
            options.SerializerSettings.Converters.Add(new BsonValueConverter());
            options.SerializerSettings.Converters.Add(new BsonJavaScriptWithScopeConverter());
            options.SerializerSettings.Converters.Add(new BsonMaxKeyConverter());
            options.SerializerSettings.Converters.Add(new ObjectIdConverter());
        }); 
    }
}

现在,您可以使用默认的序列化程序进行序列化:

return Created($"resource/{document["_id"].ToString()}", document);